Tuaregs and Islamists fight over northern Mali, thugs attack protesters in Egypt, and more

This show is made up entirely of amateur images. We've seen time and time again how images captured by ordinary citizens then uploaded onto the Web can change history, or at least shift the balance of power. This week, we take a look back at some of those moments.

STORY 1: Mali

We begin today in Mali, West Africa. The entire northern part of the country has been overrun by rebels. They're a mixture of fighters from the nomadic Tuareg people and members of a local Islamist group called Ansar Dine, "Defenders of Faith." The Tuareg forces, the MNLA, have declared the independence of the region - and they're done fighting for now. But the Islamists want to keep going, take the whole country, and make it into an Islamic state. Not many journalists have been able to get to the region. We frankly don't know exactly what's going on. Our Observer Assan Midal lives there, in the town of Gao. He tells us that the two sides might have started out fighting together, but now they're rivals.

STORY 2: Egypt

Next up, the baltagiya of Egypt. Repressive regimes often use non-official militias to do their dirty work. In Syria so-called 'shabiha' militias have been helping Bashar al-Assad put down the protests. In Iran the 'basij' has played a similar role. And in Egypt you've got the baltagiya. They are thugs-for-hire, used by the Mubarak regime for years, to beat up and intimidate political dissidents. They're the ones who famously stormed Tahrir Square on horses and camels during the revolution. Mubarak is gone now of course, but activists say the baltagiya are still being used by the military council that replaced him. Our Observer Mostafa Kandil was in Cairo's Abbasiya neighborhood on May 2 when the baltagiya attacked, killing at least 9 people, possibly many more. He saw the damage they inflicted.

STORY 3: World

Next up, a look at some of the images sent in this week by our Observers.

First stop, Congo, in Central Africa, with Alain Wandimoyi. He lives in the eastern part of the country, which went through a decade of complex, messy, deadly conflict after the Rwandan genocide. Today there's fighting again: the Congolese army is hunting down a renegade general known as the Terminator, who's wanted for war crimes. And as always, it's the civilians who suffer most. Alain sent us pictures showing the inhabitants of a village fleeing in a hurry. It's no way for people to live, says Alain, in a region that is rich in natural resources like gold. The renegade general is believed to control several mines - a reminder that natural bounty too often leads to war, not peace.

Staying in Africa, we head west to Burkina Faso. Our observer Frédéric Gnoumou lives in the country's second-largest city. That's where he took this photograph. 265 six-year-olds in one classroom... School enrollment has exploded ni the last few years with Burkinabé families fleeing war in neighboring Ivory Coast. Frédéric says one problem is the schools accepting new kids because their parents offer bribes. He hopes his picture will make the authorities take action.

We finish in Saudi Arabia, with Mohammad al-Saeedi, who told us about this video, filmed during a wedding. It's become a tradition to celebrate a wedding by unloading automatic weapons into the air. It's dangerous, and theoretically banned by law... but not in practice.